抄録
The validity of animal pain assessment still remains a matter of debate. In the present study, we hypothesized that pin-evoked a complex hyperalgesic-type response is a more clinically relevant indicator for analgesic effect than simple withdrawal from von Frey tactile stimulation in rats after peripheral nerve injury. To test this hypothesis, we investigated the effects of pregabalin and NK1 antagonist CP-99994, as an example of a standard neuropathic pain treatment and an analgesic active in animal models but not in neuropathic pain patients, respectively. Administration of pregabalin (30 mg/kg, p.o.) resulted in analgesic effects in both von Frey and pin test with similar potency. On the other hand, CP-99994 (100 mg/kg, p.o.) showed analgesic effects in von Frey test, but not any effects in pin test. Our results indicated that pin-evoked a complex hyperalgesia-type response is one of translational and appropriative analgesic measurements in rats after peripheral nerve injury.
